describe the fluid mosaic membrane structure( 15 marks)
The liquid-mosaic structure of the membrane consists of a liquid bilayer of lipids in which protein molecules are immersed at different depths. Protein molecules are only able to swim laterally in the bilayer, forming in it a kind of mosaic that constantly changes its pattern. Membrane proteins can be integral (penetrating the membrane through), semi-integral (immersed at one end into the outer or inner lipid layer), surface (located on the outer or adjacent to the inner sides of the membrane).
The lipid bilayer consists of phospholipids and glycolipids, the molecules of which are composed of hydrophobic tails and hydrophilic heads.
The hydrophilic heads of lipids are turned outward - towards the aqueous contents of the cell and towards the external aqueous medium. The hydrophobic tails are turned inside the bilayer.
Branched oligosaccharide chains are attached to some proteins and lipids from the outside of the membrane, forming the cell glycocalex